The stock (NYSE: STZ) was trading midday at $44 a share, up from Wednesday’s close of $40.80. The shares hit a new 52-week high.

The terms of the new deal calls for AB InBev to sell Modelo's Piedras Negras brewery in Mexico, next to the U.S. border, to Constellation and grant it perpetual rights for Corona and other Modelo brands in the United States, at a cost of $2.9 billion.

Constellation still would acquire the 50 percent of its Crown Imports LLC joint venture it did not own for $1.85 billion. Crown is a 50-50 venture with Grupo Modelo.

AB InBev and Constellation have agreed to a three-year transition, during which Constellation plans to invest $400 million to expand Piedras Negras' capacity to enable it to supply 100 percent of U.S. needs, up from 60 percent today.

AB InBev would supply Constellation with beer, cans and information technology support over this period. Constellation would have the option to extend the beer supply period for up to two more years.

"The revised agreement with AB InBev will make Constellation's Crown beer division a fully independent competitor and the third-largest producer and marketer in the U.S. beer industry,” said Robert Sands, Constellation Brands president and CEO, in a statement. “This is a transformational acquisition for our company as we will hold perpetual rights to Corona and the Modelo brands distributed by Crown in the U.S.”

The U.S. Department of Justice this month filed a lawsuit seeking to stop AB InBev from buying the half of Grupo Modelo it did not already own, saying the multibillion deal would lessen competition in the U.S. beer market.

Constellation Brands had planned to acquire the remaining half of its Crown Imports LLC joint venture in a $1.85 billion deal. Last year, Constellation Brands announced the Crown Imports deal with Anheuser-Busch, which would give Constellation total control of distribution of popular Corona beers, among other products, in the United States.